Is it possible to change the DND on screen message system wide in CUCM 7.1 as users are getting ??? on screen when they hit the DND button.ThanksGlenn

I am having a problem with Plantronics headsets, the model is plantronics - w01a, and the system version that we are using is CUCM version 7.1.3.10000-11. I am connecting the headsets to a Cisco 7961 with the following phone load SCCP41.8-5-2SR1S.The...